Combined oral contraceptive use before the first birth and epithelial ovarian cancer risk.
|Authors||Linda S Cook, Claire R Pestak, Andy Cy Leung, Helen Steed, Jill Nation, Kenneth Swenerton, Richard Gallagher, Anthony Magliocco, Martin Köbel, Angela Brooks-Wilson & Nhu Le|
|Abstract||BACKGROUND: Combined oral contraceptive (COC) use reduces epithelial ovarian cancer (EOC) risk. However, little is known about risk with COC use before the first full-term pregnancy (FFTP). METHODS: This Canadian population-based case-control study (2001-2012) included 854 invasive cases/2139 controls aged ⩾40 years who were parous and had information on COC use. We estimated odds ratios (aORs) and 95% confidence intervals (CI) adjusted for study site, age, parity, breastfeeding, age at FFTP, familial breast/ovarian cancer, tubal ligation, and body mass. RESULTS: Among parous women, per year of COC use exclusively before the FFTP was associated with a 9% risk reduction (95% CI=0.86-0.96). Results were similar for high-grade serous and endometrioid/clear cell EOC. In contrast, per year of use exclusively after the FFTP was not associated with risk (aOR=0.98, 95% CI=0.95-1.02). CONCLUSIONS: Combined oral contraceptive use before the FFTP may provide a risk reduction that remains for many years, informing possible prevention strategies.|
|Journal Name and Citation||
Br J Cancer. 2017 Jan 17;116(2):265-269. doi: 10.1038/bjc.2016.400. Epub 2016 Dec 13.
|Date of Publication||2016/12/13|